TUESDAY, Nov. 8, 2016 (HealthDay News) -- Only about half of U.S. family doctors follow guidelines on screening patients for prediabetes, a new study finds.

More than one-third of American adults have prediabetes, and most don't know it.

Prediabetes means that blood sugar levels are higher than normal but not high enough to be diabetes. Diagnosing and treating prediabetes can prevent patients from developing diabetes, a leading cause of death in the United States.

University of Florida researchers surveyed more than 1,200 family doctors in academic medical settings nationwide. They found that those doctors with a positive attitude toward prediabetes as a clinical condition were more likely to follow national screening guidelines and offer treatment for their patients. Prediabetes treatments include medicine, exercise and losing weight.

Other doctors were more likely to suggest their patients make general lifestyle changes that may reduce heart disease risk, but aren't associated with lowering blood sugar levels.

Doctors also cited patients' ability to make lifestyle changes, stay motivated and economic resources as significant barriers to preventing diabetes.

The study was published Nov. 8 in the Journal of the American Board of Family Medicine.

"Some physicians think that a prediabetes diagnosis 'overmedicalizes' patients, and some believe it is best to focus on providing general advice on healthy lifestyle," study author Arch Mainous III said in a university news release. Mainous is chairman of health services research, management and policy in the College of Public Health and Health Professions.

The American Diabetes Association recommends prediabetes screening for adults who are overweight or obese and after age 45. The U.S. Preventive Services Task Force recommends screening for people between 40 and 70 years of age who are overweight or obese.

"I'm hoping that we can change physician attitudes so that they follow and trust the screening and treatment guidelines, which are evidence-based, and view it as a worthwhile way to prevent diabetes," Mainous said.